1. Field of the Invention
The invention relates to a controlled, remote dispensation of fluids and other materials and, more particularly, to a method and system for controlling a dispensation of fluids including a remote communication link between a central controller and at least one metered valve apparatus.
2. Description of the Related Art
In large automotive repair and servicing facilities, such as car dealerships, fluids such as motor oil and transmission fluid are stored in bulk and are dispensed for use in individual vehicles.
In accordance with one prior art system, each of the bulk fluid tanks are coupled to individual work stations or bays by flow lines including a metering device. In addition, associated with each work station or bay is an electrically operated valve and a manual valve. At the Parts Department of the facility, a thumb wheel electromechanical device is set to the number of quarts of fluid (such as oil) to be dispensed, and the electromagnetic valve associated with one bay is opened. Wires extend from the Parts Department to the electrical valve at each work station or bay, to provide actuation of the electrical valve, thus enabling fluid flow to the selected work station or bay. Then, when the manual valve at the work station is opened to dispense oil, the metering device sends signals back to the thumb wheel device, successively stepping it toward zero as the oil is dispensed. When the device is reset to zero, the electrical valve is closed and oil flow is stopped.
The foregoing relatively primitive system involves the need for telephone calls from the work station to the Parts Shop or vice versa when the dispense operation is completed, and delays when the mechanics at several bays are requesting the dispensing, of fluids, or do not promptly dispense fluid following energization of the electromagnetic valves. Further, because no automatic record is made of the fluid dispensing, many facilities have encountered very substantial losses of valuable fluids, both during and after office hours.
Prior art uses a manually-operated controller. The operator uses a switch to select which station to pump to. This selects both the service bay and the fluid dispensed. The controller then counts clicks from a flow meter in that line.
Prior art systems are further characterized by the following disadvantages:
a. Only one dispense at a time. PA1 b. Small number of fluids/stations per controller. PA1 c. No queuing possibility: constant attention to operator required if jobs area to be sequenced. PA1 d. Adding fluids/stations usually requires adding separate controllers at the control point since each controller only accommodates 8 fluid-stations. PA1 e. A maze of wiring fans out from controller to each building in which there is a dispense-point. This wiring can be difficult to install, requiring either trenching to bury it or elevated wiring to allow passage of vehicles under it. PA1 f. Due to the necessary wiring, actual dispense points must be near the controller. PA1 g. The only intelligence in the system is the control operator who must queue the jobs and determine when the job has finished pumping (the full quantity may not actually be needed, as when a transmission is being topped off). The operator usually has no visibility when a technician has stopped pumping short of the specified quantity. The operator also does not know if a technician requesting a dispense has walked away from the dispensing station or otherwise abandoned the requisite dispense. The operator is responsible for billing the correct amount of fluid to the correct job, a task which is often imprecisely performed at best. PA1 h. If power to the controller is interrupted, the dispense stops and it may or may not be able to be resumed when power is restored. PA1 i. Present controllers do not start and stop pumps. Pumps are left on and fluid lines are constantly under pressure. PA1 j. Present system have a one-tenth quart step size; each click represents 1/10 quart of fluid. PA1 k. Present systems do not maintain or provide any inventory information. In fact, present systems will initiate a dispense even if there is no fluid in the tank to dispense. PA1 l. Present systems provide no record-keeping or billing information. PA1 m. Present systems provide no password protection or other authorization authentication, and keep no records of who has initiated a dispense. PA1 n. No automatic fire response is included in present systems. PA1 a. Allows as many simultaneous dispenses as there are flow meters in the system. If each fluid at each bay has a separate flow meter, all stations may pump all fluids simultaneously. PA1 b. Allows a virtually unlimited number of fluids and stations. PA1 c. Queues all dispenses so that operator attention is only required to initiate the dispense. Automatically sequences dispenses which use the same flow meter without operator intervention. PA1 d. Adding fluids or stations does not require adding anything at the control point. PA1 e. The control PC is linked by radio or telephone to the Remote Controllers (RCs), eliminating a large wiring headache between buildings. PA1 f. Buildings may be separated from the Control point by up to a mile or so with radio-interconnect, or by many miles with telephone interconnect. PA1 g. Intelligence (computers) are placed at two points in the system, greatly reducing operator workload and attention, and avoiding dependence on operator memory. PA1 h. Power interruption at the Control PC does not interrupt or interfere with already-authorized dispenses. The RC will finish them and retain the results in memory until the Control PC comes back on-line. Power interruptions at the RC will cause temporary interruption of operating dispenses because of lose of control of valves and pumps, but the system can be made to pick up where it left off when power is restored. PA1 i. Pumps can be started and stopped with each dispense, or the system can automatically accommodate a "pumps-always-on" system. PA1 j. This system can provide 1/20th quart visibility if symmetric-switched flow meters (equal on and off times) are used. PA1 k. A current inventory, once entered by the operator, is maintained by the system, with re-order indications to the operator at user-controlled inventory points. A dispense cannot be initiated without sufficient inventory on hand. PA1 l. Extensive record-keeping and billing information is available from this system. PA1 m. The system provides password protection at several levels. Each dispense must be authorized by a named person, which is recorded. PA1 n. The system interconnects with the user's fire alarm system, providing automatic shutdown of all pumping in a building which experiences a fire. All fluid dispensed at the time of a fire-induced shutdown is still reported to the Control PC, but pumps and valves are turned off to prevent spraying fire-enhancing fluids from ruptured lines. Alternatively, an automatic fire-extinguishing system may be activated by an RC whose alarm is triggered.
Accordingly, an object of the present invention is to provide a method and system for controlling a dispensing of fluids characterized by the following advantageous features: